﻿using System;
using System.IO;
using System.Security.Cryptography;
using System.Text;
using System.Web.Security;

namespace Ledict.Utility.Extension
{
    /// <summary>
    /// 加密扩展类
    /// </summary>
    /// <remarks>
    /// Create Date:2011-11-18
    /// Author:陈重
    /// Version
    /// Edit Date:2014-02-03
    /// Edit Author:Zhangpeng
    /// </remarks>
    public static class CryptoExtensions
    {
        #region Method
        /// <summary>
        /// 字符串md5加密
        /// </summary>
        /// <param name="src">
        /// 原始字符串
        /// </param>
        /// <returns>
        /// 加密结果，为大写
        /// </returns>
        public static string ToMD5(this string src)
        {
            return FormsAuthentication.HashPasswordForStoringInConfigFile(src, "MD5");
        }


        /// <summary>
        /// 进行DES加密。
        /// </summary>
        /// <param name="pToEncrypt">
        /// 要加密的字符串。
        /// </param>
        /// <param name="sKey">
        /// 密钥，且必须为8位。
        /// </param>
        /// <returns>
        /// 以Base64格式返回的加密字符串。
        /// </returns>
        public static string DESEncrypt(this string pToEncrypt, string sKey)
        {
            using (DESCryptoServiceProvider des = new DESCryptoServiceProvider())
            {
                byte[] inputByteArray = Encoding.UTF8.GetBytes(pToEncrypt);
                des.Key = Encoding.ASCII.GetBytes(sKey);
                des.IV = Encoding.ASCII.GetBytes(sKey);
                var ms = new MemoryStream();
                using (CryptoStream cs = new CryptoStream(ms, des.CreateEncryptor(), CryptoStreamMode.Write))
                {
                    cs.Write(inputByteArray, 0, inputByteArray.Length);
                    cs.FlushFinalBlock();
                    cs.Close();
                }

                string str = Convert.ToBase64String(ms.ToArray());
                ms.Close();
                return str;
            }
        }


        /// <summary>
        /// 进行DES解密。
        /// </summary>
        /// <param name="pToDecrypt">
        /// 要解密的以Base64
        /// </param>
        /// <param name="sKey">
        /// 密钥，且必须为8位。
        /// </param>
        /// <returns>
        /// 已解密的字符串。
        /// </returns>
        public static string DESDecrypt(this string pToDecrypt, string sKey)
        {
            byte[] inputByteArray = Convert.FromBase64String(pToDecrypt);
            using (var des = new DESCryptoServiceProvider())
            {
                des.Key = Encoding.ASCII.GetBytes(sKey);
                des.IV = Encoding.ASCII.GetBytes(sKey);
                var ms = new MemoryStream();
                using (CryptoStream cs = new CryptoStream(ms, des.CreateDecryptor(), CryptoStreamMode.Write))
                {
                    cs.Write(inputByteArray, 0, inputByteArray.Length);
                    cs.FlushFinalBlock();
                    cs.Close();
                }

                string str = Encoding.UTF8.GetString(ms.ToArray());
                ms.Close();
                return str;
            }
        }
        #endregion
        

    }
}